Robert Downey Jr. Has Some Advice for Charlie Sheen (VIDEO)

Robert
Downey Jr. is a former Hollywood "bad boy." The actor was known for
his hard-partying ways, but now, Downey is clean and sober -- and he stays out
of trouble. But there's always someone ready to fill the "bad boy"
vacuum. Recently, that person seems to be Charlie Sheen.

This
Friday, the cops came to Sheen's hotel room, after the actor allegedly went on
a drunken coke-fueled rampage. Sheen also allegedly had a naked hooker locked
in his room's closet. This is a big scandal for the 'Two and Half Men' star. So
on 'Late Show' (weeknights, 11:35PM ET on CBS), David Letterman turned to his
expert on drugs, booze and scandals -- Mr. Downey himself.